package j2024.j202408;

public class j0830 {
    int[] dx = {0,0,-1,1};
    int[] dy = {1,-1,0,0};
    int m,n;
    boolean[][] vis;
    int count;

    /**
     * 695. 岛屿的最大面积
     * @param grid
     * @return
     */
    public int maxAreaOfIsland(int[][] grid) {
        m = grid.length;n = grid[0].length;
        vis = new boolean[m][n];
        int ret = 0;
        for (int i = 0; i < m; i++) {
            for (int j = 0; j < n; j++) {
                if(grid[i][j]==1 && !vis[i][j]){
                    count = 0;
                    vis[i][j] = true;
                    dfs(grid,i,j);
                    ret = Math.max(count,ret);
                }
            }
        }
        return ret;
    }
    public void dfs(int[][] grid,int i,int j){
        count++;
        for (int k = 0; k < 4; k++) {
            int x = i+dx[k],y = j+dy[k];
            if(x>=0 && x<m && y>=0 && y<n && grid[x][y]==1 && !vis[x][y]){
                vis[x][y] = true;
                dfs(grid,x,y);
            }
        }
    }
}
